1. Field of the Invention
The present invention relates to a camera provided with data imprinting device for imprinting photographic data such as a date, time, shutter speed, aperture value, etc., on film.
2. Description of the Related Art
A camera provided with a data imprinting device which stores photographic data such as a date, time, shutter speed, aperture value, etc., in a memory each time the shutter is released and subsequently reads out the stored data to imprint the same on film in predetermined areas thereof at the time of rewinding the film, is known in the art. In such a camera, it is necessary to detect the trailing edge of the last frame in order to imprint photographic data on each frame precisely in a predetermined area thereof. A method of detecting the trailing edge of the last frame is disclosed in Japanese Laid-open Patent Publication No.63-177120 in which two pulses of different phases are generated by a mechanism composed of a gear, a printed circuit board, and a brush which slidably contacts the printed circuit board. The gear rotates in accordance with the movement of the film to rotate the brush relative to the printed circuit board so that the levels of the two pulses become high simultaneously only at each moment the border between two adjacent frames passes a predetermined position. The trailing edge of the last frame is detected at the time of rewinding the film by monitoring the levels of the two pulses. However, since there is a certain period of time required for the levels of the two pulses to become high simultaneously, the trailing edge of the last frame cannot be detected precisely. Accordingly, such a conventional method of detecting the trailing edge of the last frame is not suitable for the case where photographic data is imprinted on film in a narrow area between two adjacent sprocket holes thereof.